This project is related to NIMH research topic number 115-B-7. It is a proposal to manufacture a multi-neuron recording system capable of simultaneously detecting, amplifying, filtering, digitizing, isolating, and recording over a hundred neurons from the brains of behaving animals. Goals include (1) to provide many channel acquisition at a significantly lower cost than competing systems, (2) to support several microelectrode acquisition methods including tetrodes, (3) to provide advanced tools for behavioral experiments including on-line spike-sorting and experimental design, (4) to offer an open and extensible architecture for researchers to build on, and (5) to provide a complete solution including not only the acquisition system, but also amplifiers, preamplifiers, cable, connectors and headstages. Such a multi-neuron recording system can improve the efficiency of data collection yielding more single-unit neuronal recordings in an experimental session. More importantly, it extends the researcher's capabilities from the level of single cell analysis to that of neural ensembles believed to be the functional units of information processing in cortical areas of the brain. This technology will facilitate the study of representation and communication in neural networks associated with behavior, improving our understanding of biological information processing and thus supporting NIMH's research mission. PROPOSED COMMERCIAL APPLICATION: This research canbe applied to producing, a data acquisition system for recording from large ensembles of single neurons in behaving animals.